KNOWN AND POTENTIAL TOXICITIES: Since DITPA is a thyroid hormone analogue with thyromimetic actions, safety and side effect profiles may be similar to those observed with thyroid hormones T3 and T4 preparations (e.g., liothyronine and levothyroxine). Although excess thyromimetic action is a theoretical side effect, it is also possible that tissue-specific hypothyroidism might result if the drug fails to have sufficient thyromimetic activity in a particular tissue. Due to pituitary effects of DITPA, a secondary lowering of TSH may result, which in turn may lead to decreased endogenous production of T4. The potential effects of such theoretical biochemical changes are unknown. Thus, DITPA safety will be diligently monitored throughout the study through multiple examinations, symptom scales, and laboratory evaluations.